定价： 983元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

4.1 CCl4 and CHCl3 may be present in trace amounts in liquid chlorine. The use of chlorine to purify water would then transfer these compounds to the water. Therefore, when the concentrations of the CCl4 and CHCl3 in the liquid chlorine are known, the maximum amounts contributed to the water by the chlorine can be estimated.1.1 This test method is designed for the determination of carbon tetrachloride (CCl4) and chloroform (CHCl3) in liquid chlorine. The lower limit of detection is dependent on the sample size and the instrument used; five ppm (w/w) is achievable.1.2 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off in accordance with the rounding-off method of Practice E29.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazards statements are given in Section 7 and in 9.2.3.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 加购物车

定价： 646元 加购物车

定价： 590元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

定价： 646元 加购物车

定价： 571元 加购物车

4.1 Standard wedge welding devices rely on the operator to properly adjust the welding parameters (temperature, speed, and pressure) which are needed to create a sound weld. Changes in one or more of these parameters during production seaming, whether deliberate or accidental, can lead to poor weld quality. Prior to data acquisition systems, verifying welding parameters throughout the welding process relied solely on periodic visual observations and documentation, leaving substantial room for error. This ASTM standard practice, which requires a data acquisition system to be installed on thermal fusion welding devices, allows for the recording of these welding parameters along the entire length of the welded seam at pre-determined intervals, throughout the entire thermal fusion seaming process.4.2 The acquired data can be used in the construction quality control / construction quality assurance program to compare the welding parameters at recorded locations along the welded length to preset values, such as the values obtained during the trial seam, to facilitate detection of anomalies anywhere on the welded length.4.3 This practice does not cover the precision of the measurement, that is, the accuracy of the recorded values of temperature, speed, pressure, or position on the site. It is limited to the data acquisition process.4.4 Data acquisition parameters, such as the frequency at which the data are recorded, may be adjusted by the user depending on project specifications.1.1 This practice establishes the minimum required data recording, saving, and reporting requirements for data acquisition devices used in thermal fusion welding of geomembrane systems. Thermal fusion welding devices may include hot-wedge or hot-air wedge welders. From the data collected using this practice, it is possible to compare the welding parameters used on any production weld to those obtained during the trial welding and to the set welding parameters. This practice does not purport to identify the quality of any given weld. This standard can be used for all geomembranes, homogeneous or scrim reinforced, that can be seamed by thermal fusion welding methods.1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This procedure may be used to assess the in vitro reduction of a microbial population of test organisms after exposure to a test material.1.1 This test method measures the changes of a population of aerobic and anaerobic microorganisms within a specific sampling time when tested against antimicrobial test materials in vitro. The organisms used are standardized as to growth requirements and inoculum preparation and must grow under the conditions of the test. The primary purpose of this test method is to provide a set of standardized conditions and test organisms to facilitate comparative assessments of antimicrobial materials miscible in aqueous systems.1.2 This test method allows the option of using a test sample size of 10 mL or 100 mL.1.3 Knowledge of microbiological techniques is required for this procedure.1.4 Aseptic technique should be practiced at all times.1.5 In this test method, SI units are used for all applications, except for distance in which case inches are used and SI units follow in parentheses.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 加购物车

5.1 This test method provides a relatively simple and reliable microscopical means of measuring the phase abundance of portland cement clinker (Note 1). Microscopical point counting provides a direct measure of the clinker phase composition in contrast to the calculated Bogue phase composition (Note 2).NOTE 1: This test method utilizes a reflected light microscope. Related methods such as transmitted light microscopy, scanning electron microscopy, and automated imaging techniques may also be used for clinker analysis but are not presently included in this test method.NOTE 2: This test method allows direct determination of the proportion of each individual phase in portland cement clinker. This test method is intended to provide an alternative to the indirect estimation of phase proportion using the equations in Specification C150/C150M (footnote C in Table 1 and footnote B in Table 2).5.2 This test method assumes the operator is qualified to operate a reflected light microscope and the required accessories, is able to correctly prepare polished sections and use necessary etchants, and is able to correctly identify the constituent phases.5.3 This test method may be used as part of a quality control program in cement manufacturing as well as a troubleshooting tool. Microscopic characterization of clinker phases may also aid in correlating cement properties and cement performance in concrete, to the extent that properties and performance are a function of phase composition.1.1 This test method covers a systematic procedure for measuring the percentage volume of the phases in portland cement clinker by microscopy.1.2 The values stated in SI units are to be regarded as the standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 加购物车

5.1 Withdrawal or injection well test field procedures are used with appropriate analytical procedures in appropriate hydrogeological sites to determine transmissivity and storage coefficient of aquifers and hydraulic conductivity of confining beds.5.2 Practice D3740 provides evaluation factors for the activities in this test method.NOTE 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.5.3 This test method may be limited due to the correspondence between the field situation determined by this test method and the simplifying assumptions of the analytical Test Methods D4105/D4105M or D4106 and D4043.1.1 This test method covers the field procedure for selecting well locations, controlling change (discharge or injection) rates, and measuring water levels used to analyze the hydraulic properties of an aquifer or aquifers and adjacent confining beds.1.2 This test method is used in conjunction with an analytical procedure such as Test Methods D4105/D4105M or D4106 to evaluate the data and determine aquifer properties.1.3 The appropriate field and analytical procedures are selected as described in Guide D4043.1.4 Limitations—The limitations of this test method are primarily related to the correspondence between the field situation determined by this test method and the simplifying assumptions of the analytical Test Methods D4105/D4105M or D4106 and D4043.1.5 Units—The values stated in SI units are to be regarded as standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard.1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.6.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design.1.7 This test method offers a set of instructions for performing one or more operations. This document cannot replace education or experience and should be used in conjunction with professional judgement. Not all aspects of this standard may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a projects many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 加购物车

5.1 Constant drawdown test procedures are used with appropriate analytical procedures to determine transmissivity, hydraulic conductivity, and storage coefficient of aquifers.NOTE 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors: Practice D3740 provides a means of evaluating some of those factors.1.1 This practice covers the methods for controlling drawdown and measuring discharge rates and head to analyze the hydraulic properties of an aquifer or aquifers.1.2 This practice is used in conjunction with analytical procedures such as those of Jacob and Lohman (1)/(2),2 and Hantush (3).1.3 The appropriate field and analytical procedures for determining hydraulic properties of aquifer systems are selected as described in Guide D4043.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.1.5 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.

定价： 515元 加购物车

5.1 Assumptions:  5.1.1 Well discharges at a constant rate, Q. 5.1.2 Well is of infinitesimal diameter and fully penetrates the aquifer. 5.1.3 The nonleaky aquifer is homogeneous, isotropic, and aerially extensive. A nonleaky aquifer receives insignificant contribution of water from confining beds. 5.1.4 Discharge from the well is derived exclusively from storage in the aquifer. 5.1.5 The geometry of the assumed aquifer and well conditions are shown in Fig. 1. 5.2.3 Application of Theis Method to Unconfined Aquifers:  5.2.3.1 Although the assumptions are applicable to artesian or confined conditions, the Theis solution may be applied to unconfined aquifers if drawdown is small compared with the saturated thickness of the aquifer or if the drawdown is corrected for reduction in thickness of the aquifer, and the effects of delayed gravity yield are small. 5.2.3.2 Reduction in Aquifer Thickness—In an unconfined aquifer dewatering occurs when the water levels decline in the vicinity of a pumping well. Corrections in drawdown need to be made when the drawdown is a significant fraction of the aquifer thickness as shown by Jacob (5). The drawdown, s, needs to be replaced by s′, the drawdown that would occur in an equivalent confined aquifer, where: 5.2.3.3 Gravity Yield Effects—In unconfined aquifers, delayed gravity yield effects may invalidate measurements of drawdown during the early part of the test for application to the Theis method. Effects of delayed gravity yield are negligible in partially penetrating observation wells at and beyond a distance, r, from the control well, where: After the time, t, as given in Eq 9 from Neuman (6). where: Sy   =   the specific yield. For fully penetrating observation wells, the effects of delayed yield are negligible at the distance, r, in Eq 8 after one tenth of the time given in the Eq 9. Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors. 1.1 This practice covers an analytical procedure for determining the transmissivity and storage coefficient of a nonleaky confined aquifer. It is used to analyze data on water-level response collected during radial flow to or from a well of constant discharge or injection. 1.2 This analytical procedure, along with others, is used in conjunction with the field procedure given in Test Method D4050. 1.3 Limitations—The limitations of this practice for determination of hydraulic properties of aquifers are primarily related to the correspondence between the field situation and the simplifying assumptions of this practice (see 5.1). 1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026. 1.4.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design. 1.5 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 加购物车

定价： 590元 加购物车